Intraarticular Central Compartment

The perineal post is heavily padded and lateralized against the medial thigh of the surgical hip. This aids in achieving the optimal traction vector (Fig. 2) and reduces direct pressure on the perineum, lessening the risk of neuro-praxia of the pudendal nerve. Neutral rotation achieves a constant rela-

Fig. 2. The optimal vector for distraction is oblique relative to the axis of the body, and more closely coincides with the axis of the femoral neck than the femoral shaft. This oblique vector is partially created by abduction of the hip and partially accentuated by a small transverse component to the vector created by lateralizing the perineal post. (From Byrd JWT. The supine approach. In: Byrd JWT, editor. Operative hip arthroscopy. 2nd edition. New York: Springer; 2005. p. 145-69; with permission.)

Fig. 2. The optimal vector for distraction is oblique relative to the axis of the body, and more closely coincides with the axis of the femoral neck than the femoral shaft. This oblique vector is partially created by abduction of the hip and partially accentuated by a small transverse component to the vector created by lateralizing the perineal post. (From Byrd JWT. The supine approach. In: Byrd JWT, editor. Operative hip arthroscopy. 2nd edition. New York: Springer; 2005. p. 145-69; with permission.)

tionship between topographic landmarks and the joint. Slight flexion may relax the capsule, but excessive flexion should be avoided, as this places undue tension on the sciatic nerve and may block access for the anterior portal. Approximately 50 pounds of force is typically needed to distract the joint. In general, the goal is to use the minimal force necessary to achieve adequate

Fig. 3. The site of the anterior portal coincides with the intersection of a sagittal line drawn distally from the anterior superior iliac spine and a transverse line across the superior margin of the greater trochanter. The direction of this portal courses approximately 45° cephalad and 30° toward the midline. The anterolateral and posterolateral portals are positioned directly over the superior aspect of the trochanter at its anterior and posterior borders. (From Byrd JWT. Hip arthroscopy using the supine position. Arthroscopy 1994;10(3):275-80; with permission.)

Intra Articular Position

Fig. 3. The site of the anterior portal coincides with the intersection of a sagittal line drawn distally from the anterior superior iliac spine and a transverse line across the superior margin of the greater trochanter. The direction of this portal courses approximately 45° cephalad and 30° toward the midline. The anterolateral and posterolateral portals are positioned directly over the superior aspect of the trochanter at its anterior and posterior borders. (From Byrd JWT. Hip arthroscopy using the supine position. Arthroscopy 1994;10(3):275-80; with permission.)

distraction and keep traction time as brief as possible. (Less than 2 hours is usually considered optimal.)

PORTALS

Three standard portals are used for this portion of the procedure (Fig. 3). Two of these (anterolateral and posterolateral) are placed laterally over the superior margin of the greater trochanter at its anterior and posterior borders. The anterior portal is placed at the site of intersection of a sagittal line drawn distally from the anterior superior iliac spine and a transverse line across the tip of the greater trochanter. With careful orientation to the landmarks in relation to the joint, these portals are placed at a safe distance from the surrounding major neurovascular structures [9] (Fig. 4 and Table 1).

DIAGNOSTIC PROCEDURE

After applying traction, a spinal needle is placed from the anterolateral position, and the joint is distended with fluid. The anterolateral portal is then established under fluoroscopic control for introduction of the arthroscope (Fig. 5). Careful attention is necessary to avoid perforating the labrum or scuffing the articular surface [10]. Using the 70° scope, the anterior and posterolateral portals are then placed under direct arthroscopic view, as well as under fluoroscopy for precise

Fig. 4. The relationship of the major neurovascular structures to the three standard portals is demonstrated. The femoral artery and nerve lie well medial to the anterior portal. The sciatic nerve lies posterior to the posterolateral portal. Small branches of the lateral femoral cutaneous nerve lie close to the anterior portal. Injury to these is avoided by using proper technique in portal placement. The anterolateral portal is established first, as it lies most centrally in the safe zone for arthroscopy. (Courtesy of J.W. Thomas Byrd, MD.)

Fig. 4. The relationship of the major neurovascular structures to the three standard portals is demonstrated. The femoral artery and nerve lie well medial to the anterior portal. The sciatic nerve lies posterior to the posterolateral portal. Small branches of the lateral femoral cutaneous nerve lie close to the anterior portal. Injury to these is avoided by using proper technique in portal placement. The anterolateral portal is established first, as it lies most centrally in the safe zone for arthroscopy. (Courtesy of J.W. Thomas Byrd, MD.)

Table 1

Distance from portal to anatomic structures (based on an anatomic dissection of portal placements in eight fresh cadaver specimens)

Table 1

Distance from portal to anatomic structures (based on an anatomic dissection of portal placements in eight fresh cadaver specimens)

Portals

Anatomic structure

Average (cm)

Range (cm)

Anterior

Anterior superior iliac spine

6.3

6.0-7.0

aLateral femoral cutaneous nerve

0.3

0.2-1.0

bFemoral nerve (level of sartorius)

4.3

3.8-5.0

(level of rectus femoris)

3.8

2.7-5.0

(level of capsule)

3.7

2.9-5.0

Ascending branch of lateral circumflex

3.7

1.0-6.0

femoral artery

cTerminal branch

0.3

0.2-0.4

Anterolateral

Superior gluteal nerve

4.4

3.2-5.5

Posterolateral

Sciatic nerve

2.9

2.0-4.3

a Nerve had divided into three or more branches and measurement was made to the closest branch. b Measurement made at superficial branch of sartorius, rectus femoris, and capsule. c Small terminal branch of ascending branch of lateral circumflex femoral artery identified in three specimens. From Byrd JWT, Pappas JN, Pedley MJ. Hip arthroscopy: an anatomic study of portal placement and relationship to the extraarticular structures. Arthroscopy 1995;11:418-23; with permission.

a Nerve had divided into three or more branches and measurement was made to the closest branch. b Measurement made at superficial branch of sartorius, rectus femoris, and capsule. c Small terminal branch of ascending branch of lateral circumflex femoral artery identified in three specimens. From Byrd JWT, Pappas JN, Pedley MJ. Hip arthroscopy: an anatomic study of portal placement and relationship to the extraarticular structures. Arthroscopy 1995;11:418-23; with permission.

entry into the joint. Diagnostic and surgical arthroscopy is then achieved by interchanging the arthroscope and instruments between the three established portals. Use of both the 70° and 30° scopes provides optimal viewing, despite limited maneuverability within the joint (Fig. 6).

PERIPHERAL COMPARTMENT

After completing arthroscopy of the intraarticular compartment, the instruments are removed, the traction released, and the hip flexed approximately 45° (Fig. 7). This relaxes the capsule, providing access to the peripheral compartment.

Fig. 5. The arthroscope cannula is passed over a guide wire that was inserted through a prepositioned spinal needle. Fluoroscopy aids in avoiding contact with the femoral head or perforating the acetabular labrum. (From Smith & Nephew Endoscopy, Andover, MA. Copyright Smith & Nephew, Inc. 2003-2004; with permission.)

Fig. 5. The arthroscope cannula is passed over a guide wire that was inserted through a prepositioned spinal needle. Fluoroscopy aids in avoiding contact with the femoral head or perforating the acetabular labrum. (From Smith & Nephew Endoscopy, Andover, MA. Copyright Smith & Nephew, Inc. 2003-2004; with permission.)

Two portals are routinely used to access the peripheral compartment. These include the anterolateral portal and an ancillary portal established approximately 5 cm distally. The anterolateral portal is redirected onto the anterior neck of the femur (Fig. 8). The ancillary portal is then established distally under direct arthroscopic and fluoroscopic guidance (Fig. 9). The arthroscope and

Anterolateral Portal (Camera)

Fig. 6. (A) Arthroscopic view of a right hip from the anterolateral portal demonstrates the anterior acetabular wall (AW), anterior labrum (AL), and femoral head (FH). The anterior cannula is seen entering underneath the labrum. (B) Arthroscopic view from the anterior portal demonstrates the lateral aspect of the labrum (L) and its relationship to the lateral two portals. (C) Arthroscopic view from the posterolateral portal demonstrates the posterior acetabular wall (PW), posterior labrum (PL), and the femoral head (FH). (D) The acetabular fossa can be inspected from all three portals to view the ligamentum teres (LT) with its accompanying vessels traversing in a serpentine fashion from its more posteriorly placed acetabular attachment. (Line art from Smith & Nephew Endoscopy, Andover, MA. Copyright Smith & Nephew, Inc. 20032004; with permission. Arthroscopic images courtesy of J.W. Thomas Byrd, MD.)

(Camera)

Fig. 6. (A) Arthroscopic view of a right hip from the anterolateral portal demonstrates the anterior acetabular wall (AW), anterior labrum (AL), and femoral head (FH). The anterior cannula is seen entering underneath the labrum. (B) Arthroscopic view from the anterior portal demonstrates the lateral aspect of the labrum (L) and its relationship to the lateral two portals. (C) Arthroscopic view from the posterolateral portal demonstrates the posterior acetabular wall (PW), posterior labrum (PL), and the femoral head (FH). (D) The acetabular fossa can be inspected from all three portals to view the ligamentum teres (LT) with its accompanying vessels traversing in a serpentine fashion from its more posteriorly placed acetabular attachment. (Line art from Smith & Nephew Endoscopy, Andover, MA. Copyright Smith & Nephew, Inc. 20032004; with permission. Arthroscopic images courtesy of J.W. Thomas Byrd, MD.)

Posterolateral Portal (Camera)

Posterolateral -

Portal Femoral

(Camera) Head

instruments are interchanged, and both the 30° and 70° scopes are used for inspection (Fig. 10).

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